PMIx_Group_construct - handle error returns

[hppritcha]

trafficstars

The error return code from PMIx_Group_construct was not being handled at all. This PR fixes this issue.

In cases where the process is running without a PMIx server, for instance in a singleton program which has not invoked MPI_Comm_spawn, and it uses MPI_Comm_create_from_group the following error hep message is emitted:

---

Your application has invoked an MPI function that is not supported in this environment.

MPI function: MPI_Comm_from_group/MPI_Intercomm_from_groups Reason: PMIx server unreachable

---

If a PMIx implementation is being used that does not support PMIx_Group_construct, the following help message is emitted if the code invokes MPI_Comm_create_from_group or MPI_Intercomm_create_from_groups:

---

Your application has invoked an MPI function that is not supported in this environment.

MPI function: MPI_Comm_from_group/MPI_Intercomm_from_groups Reason: PMIx server does not support PMIx Group operations

---

Related to #10736

Signed-off-by: Howard Pritchard [email protected]

[dalcinl]

@hppritcha Could you please rebase this PR to latest main? That way, I can give it a try with mpi4py testsuite.

[hppritcha]

@dalcinl done - i wanted to do a sanity build check first.

[dalcinl]

@hppritcha FYI, all mpi4py tests passed. In the singleton case, the unsupported operation message is printed to stdout [link].

[hppritcha]

cool. Thanks @dalcinl

[hppritcha]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 1 pipeline(s).

[hppritcha]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 1 pipeline(s).